Also, Elijah with Moses appeared to them, and they were conversing with Jesus.

Mark 9:2-8.

Why Moses Was Seen

When the transfiguration occurred, Moses was “conscious of nothing at all,” for he had died centuries earlier. (Ecclesiastes 9:5, 10) Like David, he had not been resurrected and therefore was not personally present. (Acts 2:29-31) But why was Moses seen with Christ in this vision?

God had told Moses: “A prophet I shall raise up for them from the midst of their brothers, like you; and I shall indeed put my words in his mouth, and he will certainly speak to them all that I shall command him.” (Deuteronomy 18:18) Peter specifically applied this prophecy to Jesus Christ. (Acts 3:20-23) Aside from Jesus, Moses was the greatest prophet God sent to the nation of Israel.

Similarities exist between Moses and the Greater Moses, Jesus Christ. For instance, while they were infants, the lives of both of them were jeopardized by tyrannical rulers, but God saw to it that the babies were spared. (Exodus 1:20–2:10; Matthew 2:7-23) Both men spent 40 days fasting at the start of their careers as Jehovah’s special servants. (Exodus 24:18; 34:28; Deuteronomy 9:18, 25; Matthew 4:1, 2) And Moses and Jesus both performed miracles by God’s power.​—Exodus 14:21-31; 16:11-36; Psalm 78:12-54; Mark 4:41; Luke 7:18-23; John 14:11.

God used Moses to deliver Israel from Egyptian bondage, even as Jesus brings about spiritual liberation. (Exodus 12:37–14:31; John 8:31, 32) Moses was privileged to mediate the Law covenant between God and the Israelites, while Jesus is the Mediator of the new covenant. (Exodus 19:3-9; 34:3-7; Jeremiah 31:31-34; Luke 22:20; Hebrews 8:3-6; 9:15) Jehovah also used Moses to make a name for Himself before the Israelites, the Egyptians, and others, just as Jesus Christ has magnified Jehovah’s holy name. (Exodus 9:13-17; 1 Samuel 6:6; John 12:28-30; 17:5, 6, 25, 26) By having Moses appear with the transfigured Jesus, God showed that Christ would serve in these capacities on a far grander scale.

Why Elijah Appeared

Although the dead prophet Elijah had not been resurrected, it was fitting that he should appear in the transfiguration vision. Elijah did a great work in restoring pure worship and sanctifying Jehovah’s name among the Israelites. Jesus Christ did the same while on the earth and will do even more to restore pure religion and vindicate his heavenly Father by means of the Messianic Kingdom.

The prophet Malachi showed that Elijah’s work foreshadowed future activity. Through Malachi, God said: “Look! I am sending to you people Elijah the prophet before the coming of the great and fear-inspiring day of Jehovah. And he must turn the heart of fathers back toward sons, and the heart of sons back toward fathers; in order that I may not come and actually strike the earth with a devoting of it to destruction.”​—Malachi 4:5, 6.

This prophecy had its miniature fulfillment in the work of John the Baptizer. Jesus pointed this out after the transfiguration, when his disciples asked why the scribes said that Elijah must come first​—before the Messiah’s appearance. Jesus said: “Elijah, indeed, is coming and will restore all things. However, I say to you that Elijah has already come and they did not recognize him but did with him the things they wanted. In this way also the Son of man is destined to suffer at their hands.” The account adds: “Then the disciples perceived that he spoke to them about John the Baptist.”​—Matthew 17:10-13.

John did an Elijahlike work when he baptized Jews who repented of their sins against the Law covenant. More important, John was the Messiah’s forerunner and introduced Jesus Christ. (Matthew 11:11-15; Luke 1:11-17; John 1:29) But why was John’s work only a miniature fulfillment of Malachi’s prophecy?

In this vision, Elijah was seen speaking with Jesus. This was after the death of John the Baptizer, thus implying that an Elijah work would be done in the future. Moreover, the prophecy showed that this work would be done before “the great and fear-inspiring day of Jehovah.” That rapidly approaching event includes “the war of the great day of God the Almighty” at Har–Magedon, or Armageddon. (Revelation 16:14-16) This meant that the then future establishment of God’s heavenly Kingdom would be preceded by a work corresponding to the activities of Elijah and his successor, Elisha. And for over a century, Jehovah’s modern-day Witnesses have been carrying on a work involving the restoration of pure worship and the exalting of God’s name.​—Psalm 145:9-13; Matthew 24:14.